Recording viscosimeter



Dec. 1. 1953 L. M. EVANS RECORDING VISCOSIMETER SERVO MOTOR.

Filed July 24, 1951 INVENTOR. Leon M.Eu ans A-Horneg Patented Dec. 1, 1953 anconnmo VISCOSIMETER Leon M. Evans, Houston,

New York, N. I, a corporation Texas Company, of Delaware Tex., assignor to The 7 Application July 24, 1951 Serial No. .238,308

4 Claims.

This invention relates to certain improvements in viscosimeters, and more particularly to viscosimeters of the type in which the force reaction to a submerged member, rotatably driven in the l quid undergoing test, is measured to indicate the viscosity of the liquid. A viscosimeter of this general type, and on which this invention is an improvement is shown and described in the copending application of Gerhard Herzog, Serial No. 47,803 filed September 4, 1948, now Patent No. 2,643,543. Figures 4 and of the Herzog application drawings illustrate the particular type of apparatus on which this invention is an improvement.

It is often desirable to make viscosity measurements at various temperatures, generally above room temperature, and consequently a source of heat to be applied to the liquid undergoing test is necessary in most cases. One method of heating is by use of electricity, and generally a heater coil is arranged in or around th container for the liquid under test.

A problem has existed in instruments of this type of providing a satisfactory means for connecting a source of electrical energy to the heater coil, in view of the fact that the container is in substantially constant motion throughout the period of taking measurements. It has been proposed to use a pair of mercury pools as conductors but this is somewhat cumbersome, since it requires additional apparatus and space. The present invention provides a means for connecting the electric heater element surrounding the specimen cup to a source of electrical power directly through the supporting members of the specimen cup assembly. 1

The accompanying sheet of drawing shows, somewhat in diagrammatic form, a preferred embodiment of this invention. Since this invention is an improvement on the apparatus shown and described in the above identified application, only that part of the complete apparatus necessary to understand the invention is illustrated herein.'

The specimen cup I00 is rigidly mounted in a supporting yoke member H. An electric heater element I2 is mounted on the specimen cup in any suitable manner, so long as it is arranged to transfer heat to the liquid contained in the cup. A frame or base member [3 serves as a support for the entire instrument but only a part ofthe frame is shown in the drawing, The yoke member II is supported within the frame by a pair of torsion wires l4 and I5. These torsion wires are connected at their outer ends to the frame, in order to support the entire specimen cup and to any part yoke assembly in a torsionally resilient manner;

The lower torsion wire I5 is insulated fromthe frame It by means of an insulating bushing 16. A second bushing I! serves to insulate the lower torsion wire l5 from the yoke member ll. Bushings l6 and I1 are rigidly aflixed to the frame member I3 and the yoke II respectively. The

torsion wire I5 is rigidly connected to the threadedv plugs l8 and I9 which may be screwed into the bushings l5 and I! as shown. Since the upper torsion wire M is connectedelectrically to the frame and to the yoke member, the latter member may serve as a return circuit for current applied to the heater coil I 2. A short insulated lead 20 is used to connect the lower torsion wire l5 to one side of th electrical heater l2. The other side of the heater coil may be connected of the frame or yoke assembly in some convenient manner. As shown in the drawing, a short lead 2| is connected between the other side of the heater and the yoke member ll.

As shown and described in the above mentioned copending application, a rotor member 22 is mounted for rotation within the specimen cup l0. Suitable driving means (not shown) is provided for the rotor.

The upper torsion wire [4 is mounted in a bearing assembly 23 and a servomotor, shown diagrammatically on the drawing, is connected to drive the upper torsion wire in response to movements of the yoke assembly, all as shown and described in the above-mentioned application.

As will be apparent to those skilled in the art, it may often be desirable to maintain a predetermined temperature of the material within the specimen cup and this may be achieved by thermostat control of the electrical supply.

While a preferred embodiment of the invention has been shown and described herein, various modifications within the scope of the appended claims will be apparent to those skilled in the art.

Iclaim: v

1. In a viscosimeter of the type in which the force reaction to a member rotatably driven in the liquid undergoing test is measured to indicate the liquid viscosity, the combination comprising: a frame forming a support for the viscosimeter; a container for the liquid undergoing test; a rotor member supported for rotation within said container; a mechanical suspension for said container including a yoke member to which said container is rigidly attached, and a pair of torsionally resilient wires attached at one end of each to the top and bottom of said yoke member, the other ends of said wires being attached to said frame to support the container and yoke assembly in torsionally resilient fashion in said frame; insulating means interposed between at least one of said wires and said frame; an electrical heating element mounted on said container in heat exchange relation thereto; means connecting the yoke ends of said wires to said elec-' trical heater; means afioriling -conriection to the outer en'dsofsaid'wires tO"2."SOl1IC8"Of electrical energy.

2. In a viscosimeter of the type in which the force reaction to a member rotatablyedrivenin the liquid undergoing test is measured to indicate the liquid viscosity, the' combination comprising: a container for the iiduid'undergoing test; a rotor member supported for rotation within said container; a torsion suspension fior -said container including a pair of members disposed on opposite sides of said container, each of'said.

members being electrically conductive and at la t one be'ing' torsionally resilient an GIECtfiGaI heating e1ement':carried by said suspeilsidn and 4 mounted in heat exchange relation to said container; and means including said members for connecting said heating element to a source of electrical energy.

3. A combination as defined by claim 2 in which the heating element is mounted on said container in heat exchange relation thereto. "4.3K combination as dfirid'by in which the said 'members comprise a"pair of""wire-like elements.

- LEON M. EVANS.

mamas Cited in the file of this patent ifi'i n'rEnfis'rA'rEs PATENTS Name Date Palmer Dec. 30, 1941 'oTHER REFERENCES Number 

